Hello VestaCP Community,
I've got a system with VestaCP on Ubuntu 16.04 set up. The system itself works fine though since I updated the SSL certificate to a custom Let's Encrypt generated certificate, the API no longer works as expected. It always returns the values and does it's job, but the scrips of the administration panel end up with an ERR_EMPTY_RESPONSE (the server resets the connection before the "Location" header can be reached within the script).

To see if the error was caused by the PHP scripts I've set up, I hit the exact same scripts against the VestaCP demo. That was working fine, so I can confirm that it is not the PHP scripts but rather the way Vesta is configured. Now, since I didn't change anything in regards to Vesta except for the SSL cert, I find that this may be the issue. Anybody has an idea why that is? I now restored to self-signed certificates and it still doesn't seem to work (though it might be worth mentioning that those are not the original ones generated by Vesta).

Also, it might be worth mentioning that I have two other VestaCP hosts running, which are pure vanilla VestaCP and those seem to be working fine with the scripts as well.